1 From 4e9792dc8ab29175295c79c35f9f6fbd2d453b35 Mon Sep 17 00:00:00 2001
2 From: Octavian Purdila <octavian.purdila@intel.com>
3 Date: Mon, 23 Dec 2013 19:06:31 +0200
4 Subject: [PATCH] usbnet: mcs7830: rework link state detection
6 Even with the quirks in commit dabdaf0c (mcs7830: Fix link state
7 detection) there are still spurious link-down events for some chips
8 where the false link-down events count go over a few hundreds.
10 This patch takes a more conservative approach and only looks at
11 link-down events where the link-down state is not combined with other
12 states (e.g. half/full speed, pending frames in SRAM or TX status
13 information valid). In all other cases we assume the link is up.
15 Tested on MCS7830CV-DA (USB ID 9710:7830).
17 Cc: Ondrej Zary <linux@rainbow-software.org>
18 Cc: Michael Leun <lkml20120218@newton.leun.net>
19 Cc: Ming Lei <ming.lei@canonical.com>
20 Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
21 Signed-off-by: David S. Miller <davem@davemloft.net>
23 drivers/net/usb/mcs7830.c | 19 ++++---------------
24 1 file changed, 4 insertions(+), 15 deletions(-)
26 diff --git a/drivers/net/usb/mcs7830.c b/drivers/net/usb/mcs7830.c
27 index 9237c45..8dd48b5 100644
28 --- a/drivers/net/usb/mcs7830.c
29 +++ b/drivers/net/usb/mcs7830.c
30 @@ -117,7 +117,6 @@ enum {
37 static const char driver_name[] = "MOSCHIP usb-ethernet driver";
38 @@ -562,26 +561,16 @@ static void mcs7830_status(struct usbnet *dev, struct urb *urb)
40 u8 *buf = urb->transfer_buffer;
41 bool link, link_changed;
42 - struct mcs7830_data *data = mcs7830_get_data(dev);
44 if (urb->actual_length < 16)
47 - link = !(buf[1] & 0x20);
48 + link = !(buf[1] == 0x20);
49 link_changed = netif_carrier_ok(dev->net) != link;
51 - data->link_counter++;
53 - track link state 20 times to guard against erroneous
54 - link state changes reported sometimes by the chip
56 - if (data->link_counter > 20) {
57 - data->link_counter = 0;
58 - usbnet_link_change(dev, link, 0);
59 - netdev_dbg(dev->net, "Link Status is: %d\n", link);
62 - data->link_counter = 0;
63 + usbnet_link_change(dev, link, 0);
64 + netdev_dbg(dev->net, "Link Status is: %d\n", link);
68 static const struct driver_info moschip_info = {